1. Field of the Invention
The present invention relates to an apparatus for supplying chemical liquid, and more particularly, to an apparatus for supplying chemical liquid, the apparatus capable of simultaneously supplying a plurality of chemical liquids by using a plurality of nozzles that can be independently driven forward or backward and capable of enhancing processing efficiency by reducing the waiting time required to change the nozzles.
2. Description of the Related Art
Recently, semiconductor device fabrication technology is being developed to produce more highly integrated and more reliable semiconductor devices with reduced response time in order to satisfy various needs of consumers.
A conventional semiconductor device is fabricated by depositing a predetermined layer on a silicon semiconductor substrate, which is used as a semiconductor substrate, and transforming the layer into patterns having electrical properties. Here, the patterns are formed through sequential or repeated unit processes such as a layer deposition process, a photolithography process, an etching process, an ion implantation process, and a polishing process.
After each unit process is performed on the semiconductor substrate, foreign matter, such as reaction byproducts and particles that are generated during the unit process, remain on the semiconductor substrate. If the foreign matter is not removed, it becomes a source of serous errors in subsequent processes.
In particular, when a semiconductor element having a fine structure is fabricated, particles, which remain attached to a wafer after each unit process, as well as foreign matter, static electricity, watermarks, and line particles must be removed. Otherwise, they greatly affect subsequent processes. For this reason, before and after each unit process, a surface of the wafer is cleaned by using chemical liquids or distilled water.
A single-wafer-type cleaning device, which is a kind of cleaning device, cleans a substrate by rotating the substrate attached to a spin chuck while an apparatus for supplying chemical liquid, which is disposed above the substrate, supplies a cleaning solution to the substrate.
FIG. 1 is a perspective view of a conventional apparatus for supplying chemical liquid by using a chuck cylinder 20. Referring to FIG. 1, the conventional apparatus attaches one of a plurality of nozzles 10a through 10c, which supplies predetermined chemical liquid, to the chuck cylinder 20 for a cleaning process. The chuck cylinder 20, which is moved by a vertical transfer actuator 30 and a horizontal transfer actuator 40, moves the nozzle 10a, 10b or 10c attached thereto to a position above a substrate (not shown). Then, the nozzle 10a, 10b or 10c supplies the predetermined chemical liquid onto the substrate.
In the conventional apparatus, after the substrate is supplied with the predetermined chemical liquid through one of the nozzles 10a through 10c, if another chemical liquid needs to be supplied onto the substrate, the chuck cylinder 20 is moved back to where the nozzles 10a through 10c are disposed. Then, one of the nozzles 10a through 10c, which is attached to the chuck cylinder 20, is detached from the chuck cylinder 20, and another one of the nozzles 10a through 10c is attached to the chuck cylinder 20. Thereafter, the chuck cylinder 20 having the nozzle 10a, 10b or 10c newly attached thereto is moved to the substrate, so that the nozzle 10a, 10b or 10c can supply the chemical liquid onto the substrate.
Therefore, when a plurality of chemical liquids need to be used successively, processing efficiency can be reduced due to the waiting time required to change the nozzles 10a through 10c. In addition, since only one of the nozzles 10a through 10c can be attached to the chuck cylinder 20, it is impossible to simultaneously supply a plurality of chemical liquids to the substrate.